Work Item
ASTM WK86664

New Test Method for Determining the Total Porosity, Container Capacity and Air Space of a Growing Media utilizing a Porometer

1. Scope

This test method details the various required steps to be followed in order to utilize a porometer to measure total porosity, container capacity and air space of a growing media substrate utilized in container production of ornamental and agricultural crops.


growing media, physical properties


Container growers worldwide must understand the physical properties of their growing media, specifically container capacity (Water Holding) and air space of their substrate. Roots require a careful balance of both for optimal growth. The porometer, developed by NC State over 2 decades ago is utilized by professional growers and soil blenders around the world for measuring these physical properties. Third party labs charge fees to measure growing media properties utilizing the porometer. There isnt a test method for using the apparatus, only published papers detailing various parameters of the test. Significantly inconsistent results can be reported within a single lab through technician bias alone. It is imperative that we develop a test method for operating the porometer that allows for repeatability of results.

The title and scope are in draft form and are under development within this ASTM Committee.


Developed by Subcommittee: D18.22

Committee: D18

Staff Manager: Katerina Koperna

Work Item Status

Date Initiated: 06-06-2023

Technical Contact: Reid Smith

Item: 000